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November 1, 2007

Dashing Through the SnowPosted by Jim Macdonald at 12:01 AM * 154 comments

It’s getting to be that time of year when snow, frost, sleet, blizzard conditions, flurries, freezing rain, slush, ice, and “wintery mix” (See also: How many words for snow do the Eskimos have?) make driving even more hazardous than it was before.

The tires on your car are the single most important element in winter driving. They’re the interface between the vehicle and the road. The friction at that interface is what makes the car move, stop moving, and changes the direction of its movement. The more effective the friction, the better off you are.

The first thing you should know is that “all weather” tires aren’t. They’re actually all-weather-except-snow tires.

Snow tires have tread patterns and are made of rubber compositions that are markedly different from all-weather tires. Your all-weather tires are optimized for increased gas mileage. Your snow tires are maximized for friction.

Which reminds me of a joke: A couple of guys die and go up to heaven. Saint Peter meets them at the gate and says, “We’re renovating right now and your rooms aren’t quite ready. So you’ll get six more months on Earth, and you can be anything there that you want to be.”

The first man says, “I want to be a glorious golden eagle, soaring above majestic scenery,” and Poof! he’s gone. The second man says, “I want to be a real cool stud,” and Poof! he’s gone too.

Six months pass, and St. Peter calls an angel to go get the two guys. Peter says to the angel, “The first one will be easy: he’s an eagle at the Grand Canyon. The second one will be a challenge. He’s on a snow tire somewhere in Detroit.”

So, if your local jurisdiction allows it, consider studded snow tires. They really work (though the sound when you’re driving on dry pavement can be annoying). If you don’t have studded tires, or if you do, (or if you’re going to go with those all-weather specials), pick up a set of chains to keep in the trunk, and practice putting them on.

There are three kinds of friction failure that your tires can suffer. One is failure in a straight line: failure of acceleration. If the tires spin you don’t go forward. (Note: if you’re spinning your wheels, stop right now. All you’re doing is digging yourself in deeper, and making the hole you’re digging smoother and slipperier.) You can do this on dry pavement too: “smoking” your tires

Failure of braking is also a straight-line failure. That’s when you put on the brakes and keep going anyway. You can see that on dry pavement, when you get skid marks on the highway. Note: skid marks are straight. The curved marks that many people call “skid marks” are actually yaw marks, and are caused by a failure of steering.

If you find yourself skidding, take your foot off the brake and allow the vehicle to coast. Continued braking can turn a skid into a yaw, and the world will turn to dung before your eyes.

The third failure is failure of steering. Normally when you turn the wheel the front wheels turn to left or right. Wheels roll perpendicular to their axes; there’s less friction to overcome if the mass of the auto goes in that direction too. But what if the friction of the road surface is diminished? You crank over the wheel and the difference in friction isn’t enough to overcome the momentum that’s making your car tend to move in a straight line. Well, you continue in a straight line too. As you plow ahead the front end of the vehicle slows while the rear end continues at speed: the whole vehicle starts to rotate around its vertical axis and you lose any say in where your car will end up. Someplace soft would be nice. Into a tree, or into oncoming traffic, is a bit less nice.

Note too that if your brakes don’t exactly slow your tires at the same rate, the rear of the car will tend to rotate. Flat spins aren’t much fun. The best way to recover from a spin is not to get into one. Slow down.

(Sometimes, whilst driving around in the ambulance, some Jehu passes us. We wave cheerfully and say, “See you later!” Often enough, we do….)

Many American two-wheel-drive vehicles are actually one-wheel drive. One front wheel or one rear wheel. That too is a source of unbalanced forces that can lead to spinning out.

“How about four-wheel drive?” I can hear you ask. Four-wheel drive is great, but can get you going too fast for conditions and provide unwarranted confidence. Remember that all cars are four-wheel-drive when they’re braking.

Now to the driving itself: Slow the heck down. For guidelines, in a storm, on an Interstate, pretend that the speed limit is 45 MPH regardless of what the signs say. On a US or state highway, 40 MPH. On rural or lightly-traveled roads, 35 MPH. Be ready to go slower. All the way down to zero. (In whiteout conditions, get off the road and turn off your lights so the clown who’s following your lights doesn’t rear-end you.)

Ask yourself: is this trip really necessary? Be realistic. Be ready to pull over and stop at a motel if things look too hairy. Don’t only think of your own car and skill: Think of the cars and skills of the other lunatics who are out there in the middle of a winter storm.

Okay, let’s say that it’s really necessary to go, you’ve got winter tires, you’ve got chains, and you head out for the highway. Call 511 (in the USA) for travel information. Stay updated.

Drive slowly. Better late than never and all that. Leave lots of space around your car—three car lengths or more if you can. Accelerate slowly, brake slowly, and do not even consider using Cruise Control. Try to limit your travel to daylight hours. Give highway maintenance and emergency vehicles a wide berth.

Keep positive control of the wheel at all times. When you’re coming out of a turn it’s easy to just let go and let the front tires straighten themselves while the wheel slips through both your fists. In winter that can kill you. Black ice happens. For most turning, you don’t need to switch hand position at all. For larger turns, here’s how to do it: For example, in a left turn, loosen your grip with your left hand while still keeping it around the wheel. Move the right hand toward the left, with the wheel sliding through the left fist. When your hands come together, clamp down with your left hand, loosen the right, and slide it back over to the right. You may need to repeat the movement several times for a very large turn. Practice this during good weather so that it becomes natural and habitual for you.

You know those signs that say “Bridge freezes before pavement”? Believe them. Other places to watch out for ice: where a single tree shades the road while all around is sunny and bright, in a road cut with a bare rock face, and everywhere else.

“What should I keep in the trunk of my car other than those chains?” you ask. A tow strap, a sleeping bag, some of those orange-reflective safety triangles or a set of flares, and a big bag of sand. Not your smooth sandbox sand, your rougher beach sand. (Strips of carpet also work.) An extra gallon of windshield fluid. A container of “dry gas.” A flashlight. Batteries for that flashlight. A folding shovel. A windshield brush/scraper. Consider spare clothing/hat/boots.

Back when I was a Cub Scout Leader we used to make car kits in a single tin cup. The kits had:

In a tin cup:

yard-and-a-half of toilet paper

three fathoms of parachute cord

small jack knife

two heavy-duty plastic bags

chocolate

three teabags

three bouillon cubes

note paper

pencil stub

matches

match strike-strip

$0.25 phone change

compass

whistle

two nails

two needles

ten feet fishline

four fishhooks

four sinkers

The cup with its contents fit into a sandwich-sized Baggie. The entire thing went into the glove box, where it could be ignored until needed.

Here’s Field and Stream’s Altoids-tin survival kit, which can similarly be put together, put in the glove compartment, and left until needed.

Back in the day when I lived in places that got snow, we used to carry big bags of kitty litter rather than sand - not the 'scoopable' kind, but plain old clay litter. Not only could you pour it under your tires, but it added weight to the trunk (this is important if you have rear-wheel drive and a little car).

Another bit of advice, from family experience: know alternate routes. In my family's case, it was a Christmas shopping trip that involved a long, fairly steep hill; on the trip back, it was snowing and the minivan was not thrilled. We three kids piled in back, between the back door and the seat, and belted out carols and whatever other songs we had (pretty good Christmas-related memory, to be honest), and eventually my parents found a way home that didn't involve the hill.
This is not workable for every situation, but while it's nice out, keep an eye out for nasty slopes and ways around them. Even if your car is the Little Engine that Could, you may end up behind an Aerostar filled with singing children and stressed parents.

My winter driving skills are sufficient to my environment-- if I fishtail or something, the oh no make it right comes after the whee! and the actual correction. Still, the scariest driving experience I've had was a combination of braking and steering failures. Turned the wheel, car turned some but not all the way. Braking already, but car was not slowing down. I'm used to the car responding when I do something, and the snow under the tires took over.

I live the Bay Area, where the local streets get snow once every ten winters, if we're lucky. (If we're unlucky, the intervals are longer.) A few inches of snow tends not be too destructive, though considering how Californians manage to forget how to drive in the rain every damn year, I would purely hate to have them try to drive on real snow. When it does show up, at least in the city, they go out and play in it until it melts.

On the other hand, I lost control of my car one night and spun out on I-80. OMG. No snow, no rain, just tired driver.

We get black ice, though. Seen it -- never driven over it. But I know people who have. OMG.

I grew up and learned to drive in the Northeast (PA, NY, and MA) and I don't like it a lot, but I know how to do it. Now I live in the Northwest; if you stay out of the mountains here there's not usually a lot of snow, but there are places (like Portland in an easterly wind out of the Columbia Gorge and freezing conditions) where we get truly hellacious ice storms. As Jim says, traction is the name of the game. Once, driving a fairly heavy station wagon with an automatic transmission with a real stump-puller high-torque low gear I got stuck on the way to work on a patch of black ice at a traffic light. No matter that I had extra weight in the back from sandbags, that high torque would rip the tires loose from the ice no matter how gently I eased on the gas. It took me two long cycles of the light (close to 5 minutes; that was a long light) to very easily persuade the car to roll off the ice onto a patch of bare road so I could drive off. I was right in the middle of the street and I really did not want to get out and put the chains on there, having learned long ago not to trust other drivers to notice the obvious.

In general I agree with you about motorcyles, but there's one exception I know of, but haven't ever been crazy enough to try. When I was young, and still not crazy enough, I knew people who raced motorcycles on iced-over lakes in Pennsylvania in the winter. The ice was thick enough to hold the weight, and the cycles had studded tires, so unless you fell over, you couldn't possibly lose traction. At least, that's what they kept saying.

I think this is the most important point: slow the heck down. I am from Massachusetts, and it seems to me everyone forgets this lesson every year, only to re-learn it at the year's first noticeable snow. (Maybe in Montreal, or in Juneau, the no-snow season is short enough to remember, but as far north as Mass., it seems to be too short.) When it snows you need to be going at least 10 MPH under the speed limit. After a couple months worth of driving in the snow you can use your judgment, but the first snowfall or three, do not trust your judgment. Slow the heck down.

I actually do need to buy some chains for my Chevy 1500. Got the sleeping bag under the back seat, check. 300 pounds of sand in the bed, check. Tow cable, check. Gloves, both snow and leather, check. Flashlight, check. And two rolls of TP. Can't forget those.

I learned to drive with a manual transmission rear-wheel drive light (very light - early 80s Datsun/Nissan) pick-up truck in suburban/exurban (well it was exurban in the 80s, its suburban now) Detroit. So I had a bunch of fun (at least it felt like fun to my teenage-self) learning experiences with driving on snow, slush, and ice. It was particularly easy to fishtail that truck in slick conditions, and I thought I got reasonably good at doing controlled fishtails for fun, until the time I took out a couple of mailboxes at once. I thought that incident through and stopped doing intentional fishtails after that.

Then there was time a hit a patch of black ice when driving my mother's front-wheel drive sedan. I was going about 50 mph on a straight road on an early, sunny, November Saturday morning, and then suddenly I started yawing. I think one wheel hit ice and the other didn't while power was applied to the wheels. The car spun 180 degrees in the middle of the road (2-lane, no divider) before I managed to stop it. Thankfully, there was no traffic on the road at the time, nor did I slide into the roadside drainage ditches or telephone poles.

Bernard: Yeah. On the other hand, I suspect there's a little advantage to a little of that sort of thing if one lives through it. (The sort of "little" that one gets without trying, really.)

A couple of weeks ago, I was making a U-turn on El Camino here in the Bay Area, right after the second rain of the season (which had done an excellent job of lifting all the accumulated oil out of the road), and about halfway through the turn the car decided it wanted to go straight.

There's a certain advantage to having an instinctive reaction to such things that's more along the lines of blase annoyance than panic. About a lane later, the car stopped, and I finished off the now-three-point turn and went on my way.

About those snow chains, practice putting them on while wearing the kind of clothes you expect to have on in snow conditions. Knowing how to put on your chains in a warm garage with lots of light is useful, but hardly accurate to the actual weather conditions in which you would need them.

When I bought cables for my car (not enough clearance between the tire and wheel well for chains), I first practiced putting them on wearing regular work clothes, then I did it again wearing my winter parka and ski-gloves. It was a very educational experience. If there was an easy way to arrange it, I would've tried it again in the snow. As it turned out, I've not had to use them yet, but I'm certainly better aware of what it might really take to put on chains or cables under field conditions.

We seldom get enough snow here in Ireland that it sticks and makes driving difficult. Each time we do, all the bozos in 4WD SUVs think "Hooray, my 4 wheel drive finally pays for itself by making be invulnerable!".

My first car was a Nissan 280z - a RWD manual sports car. In the late 80s. In Rochester NY (The city that likes lake effect so much, it situated itself in a location to get it from two lakes). It was my graduation (from High School and Basic) present - at my request. My first winter was... interesting.

My father later commented that he figured that after one Rochester winter, I'd either have learned how to handle snow and ice, and become a pretty good driver... or I'd be dead, but he was counting on the former, because he had faith in me.

The one thing that really irks me around here is following distance - it seems that many drivers never met a gate they didn't want to tail. It's really simple. If I can't see your tires, and you're on the thruway behind me - you are too fucking close. If I can't see your headlights - especially if you're driving a sitting high SUV or Big Truck - you are way too fucking close. It's one thing if you have to bounce through a lane, or are merging in to traffic - any port in a storm, and all that. But if you're still there a mile later... you're a tailgating jerk.

My one and only snow related accident took place way back when I was commuting to college, in a huge rear wheel drive station wagon. The country road was ice/snow covered the entire route, and I nearly made it to the scraped highway when I took a curve too slowly.

Yes, too slowly. The superelevation and lack of friction, coupled with my very slow speed, pulled me right down to the ditch at the bottom of the curve.

I've driven FWD vehicles since then and never had a problem in snow/ice, even after the Great Sleet Storm of 1989. We had 7" of sleet fall, mixed with rain at times, freezing it into one massive sheet of ice. Our FWD car went right up all the hills and around all the curves, as long as I took it slow and didn't hit the brakes.

Bruce @ 14: I seriously think I just heard my helmet whimper. Doesn't 'Losing' traction imply that you have it to begin with? Because motorcycles have traction issues even when road conditions are good.

Though I suppose there are dumber things to do, especially given that the number-one cause of motorcycle crashes is careless car drivers that can't be bothered to check if the space they're trying to occupy is already in use. No cars on frozen lakes (one hopes).

Annalee @ 13 - I actually have ridden a motorcycle in the snow - but it was freshly falling, fluffy snow on well-frozen bare ground. And it was from Upper Manhattan to Brooklyn. But in general, yes, leave the two-wheeler at home in the snow.

Niall @ 21 - Even in places where it snows regularly (e.g. Long Island), lots of 4WD drivers decide that the laws of physics do not apply to them.

Here in Seattle, two things happen when it snows.
1 - Any road with a significant grade gets closed. "Do Not Enter" signs are conveniently chained to stop signs and are dragged into the middle of the road to prevent unexpected auto-slalom races.
2 - When drivers feel like they're stuck (emphasis on feel - reality has little bearing on the situation) they simply stop their car and get out and walk. No effort is made to pull over to the shoulder or to finish crossing a bridge. Stop and walk is the order of the day. Needless to say, removing all those random cars is quite a problem.

Oh, FWIW, both WalMart and Costco have stopped selling studded snow tires in WA (legal from Nov - April here IIRC) because of the damage they do to the roads.

Given my limited need to go to really snowy places, I adopt a few simple rules. Stay home. If I'm not home, don't hit the road until the craziness is over. And I carry chains - which I've never had to use.

I'm in North Texas. We tend to get ice storms rather than snow. When it does snow significantly, there's often a layer of ice underneath. A few recent transplants from up north have chains, but no one has snow tires. Yet, few people twice about getting on the road because there's "only" 1/4" of ice. I stay the heck off.

I do know how to drive in these conditions, but there are too many who don't, and that makes me literally fear for my life. People up north laugh about how we rush to the grocery stores and stock up whenever there's a slight chance of snow in the forecast, but some of us would rather be safe than dead.

13 ::: Annalee Flower Horne commented:My main mode of transport these days is a motorcycle, so all I need to know about driving on snow is 'don't.' (Any biker who hasn't figured that one out needs to go take high-school physics).

I've ridden all winter before - ice is much more of a worry than snow, by-and-large - and as long as you're not out on the road until the sun's been up for a bit, plowed roads tend to be fine.

OTOH, I was silly enough to go out early one day, and did find black ice. It was worth a giggle when I arrived to the event late, and was greeted with a sarcastic "What, late again?!? Where were you, the hospital?!?"[0], and could answer "Yes, actually".

[0] The nice thing about black ice is that you slide... so I was bruised, but neither the bike nor I were otherwise injured.

Annalee @13:
Driving a motorcycle on snow is possible, if not, er, particularly relaxing. At least, that is my experience from a new year's morning in the '90. I was on my way home after a party when the temperature dropped and it started to snow. By that time, I still had a few hundred kilometers to go, so I went on, slowly and carefully, just like all those thousands of tin boxes all around me. It worked.
But then it started to rain, and within seconds, the highway was covered with a millimeter of ice, then a centimeter, then two centimeters. By that time, I had managed to slide/ride/push my bike over to the emergency lane. 200 meters ahead of me up the hill was a rest area. It took me the better part of half an hour to reach that point, because I could hardly keep on my feet myself, let alone push the bike. Whenever I tried to walk the bike while slowly releasing the clutch lever, the rear tyre would spin wildly and my 200-plus-kilo bike would end up sideways in front of me. Fortunately, the ground was so slippery that I could just as easily swivel the whole thing back to point ahead, provided I kept it on its wheels. When it fell down once, it took me half an eternity to pick it up again.

You are so right about the roads becoming hazardous zones as soon as the snow (or ice) starts falling. Around here (Raleigh) we have a mix of Northerners (who think they KNOW how to drive on snow/ice), and Southerners who haven't seen enough snow/ice to actually learn HOW to drive on it. It makes a dangerous and sometimes deadly combination when winter gets here, and helps explain why we too head to the grocery store when we hear that winter precipitation is coming.

If it is going to snow enough to cover the roads, often I just stay home rather than risk the drive to work. If I'm at work when it snows, though, I grit my teeth and drive carefully home, staying as far from everyone else as possible.

A few years ago we had a 'light' snowfall predicted in January, but the air temp had not risen above 24 degrees for several days beforehand. Every single flake that hit the pavement stuck and didn't melt; at least until a car drove over them. Then they melted and instantly refroze, this time into a thin but slippery sheet of ice. It was Instant Chaos on the streets; within minutes every road and street in Raleigh became impassible with crashes and stuck cars all over the place.

Commutes that took less than an hour took some motorists over 10 hours to get home; I know one woman with a 10 mile drive home that took her 13 hours. Some just stayed at work overnight, schools had to keep some students there, daycares were big problems, and even EMS responders couldn't get anywhere. Lucky me; I took my wife to the dentist for some oral surgery that day and we were already home by the time the snow fell.

My main response is to switch cars. There is almost nothing you can do to a small FWD sedan to make it snow-worthy, except chains which down here are a once-every-several-years-usable sort of thing. I had a Rabbit for a while which was utterly terrifying in snow; the rear end simply had no intention of following the front, no matter what the speed.

These days we have a Saturn and a Chrysler LHS. When it snows, I drive the Chrysler; it weighs half again as much as the Saturn, and the tires are twice as wide. Driven sanely, it sticks to the road pretty well.

The big problems around here is the aggressive driving. This is one of the worst areas in the country now, maybe even worse than Boston. (Boston has more crazies, but the general level of pushiness around here is higher.) My general strategy is to find a route that is obviously bad enough to slow people down, but not so bad as to be actually impassible.

Last winter, I was driving home after work in one of the freezing-rain storms that we get around Ottawa. The main roads were okay (heavy traffic + salt) but the residential streets were a mess. A few blocks from my house, I was driving at a crawl over water-covered ice, when one of my wheels hit a spot of non-icy pavement. That moment of traction-plus-power started the car spinning and drifting across the road, and not a blessed thing I could do about it. But I figured: No other traffic, low speed, and nothing to run into in the direction I'm moving until I hit the kerb on the far side of the road, then we'll see what happens. Luckily, I was right, and the car stopped when it bumped the kerb. Once I didn't have that spin-and-slide going, I was able to resume the homewards crawl, with my heart running a lot more quickly and my eyes peeled in an attempt to spot any more non-ice under the water.

It does, actually, snow in Phoenix. Once in a blue moon. What this does to traffic on the highways does not bear mentioning, and there doesn't even need to be sticking snow or ice to cause issues. (Actually, I can't remember any snow sticking south of Cave Creek on the roads.)

The gawk factor alone is enough to cause massive accidents. We do, however, have issues with slick roads when it hasn't rained in awhile, so Jim's reminders about slippery surfaces and loss of traction apply.

However, what's really scary in Arizona are the people from Phoenix who head up the Beeline Highway to Payson whenever there's snow in the high country, just to play in it. They have no clue, inadequate tires, and a tendency to apply Phoenix driving habits to the trip. (i.e., The speed limit is equivalent to the air temperature, and if it's traveling at less than 10 mphs over the posted speed limit, flipping the driver off as you pass is required by law.)

I have family in Payson and generally decline invitations to visit when there's snow on the ground; my tires aren't adequate either, and skidding off the road on the Beeline in certain places would test the aerodynamic properties of my truck in ways I don't feel are necessary.

Oh, I also prefer strips of carpet to kitty litter. The kitty litter might get you off the ice. The strips of carpet will get you off the ice but will also provide traction if you're stuck in mud or snow. (I also have a 1' square piece of thick scrap plywood in my emergency kit. If you've got a flat or you need to jack the car up to get it unstuck from something it really sucks if the ground's not firm enough to support the jack. You can improvise with a log or rock sometimes, but that piece of plywood is just handy to have.)

Annalee Flower Horne (25):...No cars on frozen lakes (one hopes)....
Not from around here, are you?
Of course there are cars on frozen lakes, also trucks (getting building supplies to the islands and other inaccessable-by-road places).
There are stories of running train tracks across the ice to get timber, etc. from the far side.

The way it was explained to me*, under cold conditions (-15 C and lower, IIRC), the studs' pressure against the ice doesn't have time to pressure-melt the contact surface of the ice, leaving the friction at a higher value than when it's warmer. So the tires stick in the ice instead of spinning against it.

And, yes, the motorcycle rider's motto is "Traction is your friend". At a birthday party of a friend many years ago, another good friend and good bike rider climbed on his cycle and drove up the driveway to go home. About 45 minutes later we found him at the top of the drive, semi-conscious, with a bleeding head injury. He'd hit a small patch of gravel as he was coming out of the mouth of the drive and turning onto the road, going just a tad too fast, dumped the bike, and rolled into a tree. He was OK, just a mild concussion and some bruises, but he was damn near not OK at all.

And as for kamikaze car drivers vs bikes, yep. My older son has a permanently bunged-up shoulder from being pushed out of one lane into another that had an oil slick. The driver of the car never even saw him after the crash.

* Remember, I never actually tried this, and I'm quite willing to leave the experiments to those who seem to think they have less to lose.

I generally won't drive in the snow unless the actual roads are clear, now that I have clearance to work at home on "snow days." Getting out of the parking space (especially after being plowed in) is usually a bigger challenge, especially if there has been significant enough icing to make a total clearing of the tires impossible. Last year spent about 2 hours assisting husband, neighbor, and own car out of parking spaces.

Great advice. The "slow down" part is by far the most relevant here in MA, where you will always find people who think they can still drive at 75 or 80 in snow.

Moving down a few paragraphs, I would love to see a decent animation used to teach how to recover from a skid, rather than paragraph upon paragraph of (accurate but confusing) verbiage. Does anyone know of such a thing? (There is no question that "steer into the skid" is utterly incomprehensible to a large number of people, so better instructions are called for, but the linked text will be over the head of nine out of ten readers.)

Shorter winter driving :
- your brakes don't work
- neither does your steering
- stay off the accelerator
- power and torque are your enemies
- if you have a manual transmission,
drive about one-half gear higher
than you normally would

One early winter morning I took my husband to work. The job was on the west side of town, our appartment was on the east side. In the time it took to drive him to work the light rain falling in Whitehall turned to freezing rain.

On my return drive was a long long overpass. It froze. I realized this fact when I started to take the overpass at 55 mph.

The car skidded to the left almost into the overpass railing, as I corrected for that the car then skidded to the right. When this started I took my foot off the gas, and did not try to brake.

We proceed to take the rest of the overpass like a slalom run -- I finally regained complete control of the car when it had slowed to less than 5 mph. I put my flashers on and let the car crawl up the exit ramp.

When I got onto the surface street and was creeping slowly uphill to our appartment I looked up, to see a Mercedes Benz doing doughnuts down the hill coming towards me.

Fortunately, the Benz driver put his front wheels into the curb and managed to stop before he hit me. When I got home I sat and shook for an hour before taking the bus to work.

I cede that more advanced riders than me can probably handle certain kinds of snowy situations when they have to; and yeah, once the roads are plowed and sanded, it's probably not that much worse than when they're wet. As long as there's no ice and people are employing common sense. I wouldn't risk it, but then I've only been at this a couple of months.

The people who I think ought to go take a physics class are the ones who take to the twisties as if it's 65 and sunny when there's several inches of slushy, icy schlock on the road (my dad's an EMT. He makes sure I hear all the stories).

Re: cars on frozen lakes: on the same parts of the frozen lake where people are motorcycle racing? That's where the 'one would hope' comes in. One would hope people know better than to race across ice where there's other traffic.

And if you live somewhere it might possibly ever snow, buy a brush and keep it in your car (not the trunk). The number of people I've had to lend brushes to -- eventually I decided that if you were in a parking lot, you could suffer brushing snow off with your arms. Even a crappy one is better than nothing. Do not leave it in the trunk -- it's a lot easier to brush snow off one door than the entire trunk.

When I moved to Wyoming from Georgia, my boss, a native whose husband drove a snowplow, gave me winter driving tips. The most useful: If at all possible, do *not* drive in the first storm of the season. Because just about everyone has forgotten how over the summer, and there are zillions of fender-benders.

#36: If you're trying to get the car out of a spot in which it has no traction and isn't moving, what are your passengers doing in the backseat? Why aren't they pushing?
We live on a steepish hill with, thankfully, a small parking lot at the bottom ('cause some days, the car isn't going up no matter what), and if a car isn't making progress the shovellers all run over and push. Any time there's a snowstorm you can smell dying tires on our hill.

I had a friend who had moved to New York State from South Carolina. She regretted having to give up her SC plates after she had been living here for a year. She figured when she was driving through snow with SC plates, everyone gave her plenty of room; with NYS plates, she would be mistaken for someone who should know what she was doing.

Wolfa @ 47:
Thanks for reminding me it's time to put the brush and scraper in the car and change the kit in the trunk. Snow season starts in Minnesota on November first. I got my notice in the mail today about winter parking rules; not to mention the Halloween blizzard of '91 that dropped around 3 feet of snow on the city in 24 hours. Not a record for amount, just timing.

I think the most important thing about winter driving is PAY ATTENTION. Pay attention to the road itself, other drivers, and the sides of the road. Pay attention to the weather forecast and traffic reporting as relevant. No radio, except for said weather and traffic reports: find out when stations in your area do those reports, on the hour or whatever. Have minimal conversation with passengers. And yes, alternative routes to places you often travel can be very useful. Scope them out now, instead of the morning you have to be at work for a meeting and the road you usually travel is closed, or there's been an accident.

Generally I found myself nodding along, remembering when I was in New Hampshire learning to drive.

One point I learned kind of painfully is that you want to exercise caution engine-braking a front wheel drive. Basically you're balancing the vehicle on the front wheels, downshifting and turning can be a quick trip to spinout city.

Down here in Austin, authorities are occasionally showing some glimmers of clue: they shut most things down for ice storms. Which is just as well, because I live in a part of town where Diatryma's "alternate routes" are even worse than the ones of choice. There is nothing that does not involve steep grades and/or sharp blind curves, including my own driveway, which, last ice storm, I didn't dare to back down for three days.

Also, if you don't know how much tread you have left on your tires, you don't have enough.*

*in other words, if you never check, you've probably long past the point of no usable friction. To check, take a penny, place it in the tread grooves Lincoln head down. If you can still see the top of his head, you need new tires. If you can't, you may need new tires anyway.

--Listen to your tires as they drive on clear pavement. They make a distinctive noise when there's nothing but asphalt or concrete. When that noise changes to something quieter, you are on ice/packed snow.

--If you find yourself on packed snow/ice and realize you're going too fast, do nothing. Don't change direction, don't hit your brakes. Take your foot gradually off the gas. Give your car time to slow down from inertia and then change direction. This is useful if you get on a bridge and find it iced up (from the lack of noise your tires are making).

--If everything's covered in snow/ice, speed is your enemy. Keep a nice, constant, slow speed and stay away from everyone else on the road, if at all possible. Anticipate stopping, turns, lane changes, etc, at least twice as far as you'd normally anticipate doing these maneuvers, then do them carefully and without haste. Especially stay away from 4WD vehicles; many of their operators think 4WD's are immune to slipping and sliding. They are wrong.

The "Portland Car Pinball" footage should be used in a public service advert. Whenever a snowstorm is due to hit a major city where they're not used to snow, local stations should show it over and over again with the words REALLY . . . WE MEAN IT . . . . STAY . . . AT . . . HOME scrolling underneath.

Amidst this fine piece of recommendation, there was one truly awful mistake:

Consider down-shifting to allow engine compression to slow you.

Terrible idea. Never do this in slippery conditions.

First of all, the engine compression will only work on the driven wheels. Which, as Jim rightly points out elsewhere, is often much fewer than all the wheels. Worse, it's an unbalanced force, due to the vagaries of differentials. Worst is the fact that it's an almost completely unmodulated force.

In all respects, the standard braking apparatus of a car is superior for applying braking force in slippery conditions. It works on all four wheels, does so evenly, and can be finely-modulated by even those with basic driving skills. Better, most modern vehicles have intelligent apparatus to prevent skidding, and often even yawing.

But Jim's still right about taking your foot off the brake if you start to skid. And get yourself some proper tires, and slow down to maintain control.

I have accidentally stumbled upon a method for preventing (or at least improving) tailgating. I put a bicycle rack on my car. It is the sort that attaches to the tow hitch, and a metal bar extends back from the car. Something about that square metal bar pointing straight at the driver behind causes him to give me more room, so yay.

If I'm driving a stick shift in snow and ice, I will often accelerate from a standing start in 2nd gear, to reduce the torque to the wheels. This assumes of course that the transmission and engine will allow it, one of the reasons I like 4-speed manual transmissions with a reasonably low speed 2nd gear. I once actually managed a start in 3rd on a Volvo wagon that had a very nice gear ratio spread, but I bet the clutch was peeved at me.

That's nothing; I once started a 1966 Chevy truck with a 3 gear manual transmission from 2nd gear.

While it was loaded with 50 8" concrete blocks.

It wasn't deliberate; I thought for sure I was in 1st gear, and the reaction from the engine was just because of the heavy load. Once it was moving, I then tried to put it in 2nd gear and discovered I already was...

I had to do that from second when the clutch was going out on a previous car. Not fun, no. The current one is automatic, with 'low gear' being used for engine-compression braking when going down long grades - I haven't found any other use for it yet. (My parents' old Toyota pickup was geared low enough that you were in 4th gear by the time you got up to 30mph. I kept wanting to get out and push, and I was driving at the time.)

My favorite rule for driving in snow, over ice, or in other slippery conditions is simple and succinct: No Sudden Moves. If you don't have traction and try to do anything fast, you'll end up thrashing or worse. Take your time starting, stopping, and turning, and you'll have a much less unpleasant experience.

Regarding studded tires: They may give you more traction, but the ones with metal studs also do a number on the roads when there isn't a "protective" layer of snow and ice on top of them. They're also generally not legal for at least some of the year (in Oregon, they have to be off by April 1st, no foolin'). Consider other options like plastic studs and studless snow tires.

Finally, regarding tire chains: I've driven with tire chains twice, and both times it was a *miserable* experience. They're great to have in case of emergency, but if you have a choice between driving with tire chains and not driving, go with the not driving option.

On a related subject, what about cruise control in the rain? My dad sent me an email stating that if you hit a patch of water in cruise control, the engines will rev up and give you a sudden uncontrolled increase in speed. True? Or urban legend?

The first time I drove on snow was in Atlanta, in an inch of snow, and I remember how eerie it was being on the empty highway...

I am heading into my third winter in Maine and I have progressed, if one can call it that, from bug-eyed terror to "Will someone get these damn fools off the road because they can't bleeping drive on snow?!"

My difficulty is obvious to anyone familiar with Augusta, Maine: hills. I live at the top of one, on a dead end street, which slopes down to another dead end street, from which I must turn onto another steep residential street where my choices are up the hill or down the hill, before I get to a regularly plowed thoroughfare.

In my old car I'd finally gotten the knack of the controlled uphill skid - where you point the front end of the car in the right direction, hit the gas, and pray - but I bought a new(er) vehicle this year and have yet to try it in winter weather.

Also, from what I understand, tire chains are illegal in Maine, and I don't own a set of stud tires.

It might be wise for everyone who will be driving in the snow to [re]read Cold Blows the Wind Today, Jim's earlier thread on hypothermia.

All that fitting of chains and scattering of sand gets you out in the cold and the snow. And if, heaven forfend, you find yourself stuck or off the road where no one is about, remember that it's a cold hard world out there sometimes.

First of all, the engine compression will only work on the driven wheels. Which, as Jim rightly points out elsewhere, is often much fewer than all the wheels. Worse, it's an unbalanced force, due to the vagaries of differentials. Worst is the fact that it's an almost completely unmodulated force.

In all respects, the standard braking apparatus of a car is superior for applying braking force in slippery conditions. It works on all four wheels, does so evenly, and can be finely-modulated by even those with basic driving skills.

Are you sure? Engine braking is dynamically stable and thus won't lock your wheels, and can provide a pretty convenient "moderate level of braking" without requiring any driver attention at all. It also lets you do the frequently-valuable operation of "apply braking force to all wheels not being used for steering" in a rear-wheel drive vehicle. In really bad conditions you can easily get into a situation where letting off the brakes isn't enough to get the front wheels turning again and you need to straighten the steering wheel; using engine braking makes this less likely to happen.

Living in the Houston area, I don't have much opportunity to see ice or snow (except three years ago, it frickin' snowed here on Christmas Eve!) but I did have some encounters with the frigid stuff when I lived in Amarillo for a couple of years. Driving on I-40 in a blizzard in a '65 New Yorker is an experience I don't want to repeat. I didn't hit anyone, but I was schlepping around like a drunken sailor.

When we do get a rare ice storm here, I stay home. I don't want to be on the road with anyone whose sole experience with frozen H2O is in a glass of iced tea.

Snow chains intrigue me in the vague, "Oh, how quaint" manner of most foreign things to do with snow (like a definition of a "winter jacket" that's half an inch thick). I honestly don't know why, but after a lifetime on the frozen roads of Alberta, the only time I've ever seen snow chains on a car, rather than a semi, was on a Christmas holiday to Lake Tahoe (Police Officer: "Why haven't you got snow chains on?! Can't you see the road?" My mother, sheepishly: "...We're Canadian?" Officer: "Oh, all right then. Merry Christmas").

However, I think this might be a case of familiarity breeding contempt.

I'd be content with a car-mounted cell phone jammer that had a hundred yard radius. Or some sort of electronics-destroying EMP device that I could activate every time I saw some idiot yammering into his Razr while making a left turn through a yellow light at 50 miles an hour.

I want a remote that can turn off a cellphone. Not so much for use on cars (although it would be a really good idea) as on those people who have loud (and usually long) conversations in places where it's hard to get away from the sound, like mass transit. (If it can also turn off loud iPods, that would be a bonus. I shouldn't have to listen to music from eight or ten feet away, through their earbuds.)

I live in the mountains in SoCal, so often have to drive through changing conditions (dry at the bottom of the hill, ice and snow coming home.) For this sort of thing, I HIGHLY recommend Spikes Spiders instead of chains.

I've been able to be listening to a song on the radio, pull over, get out, snap on the Spiders, and listen to the end of the same song when I got back in the car. I've also pulled over to let someone pass and discovered myself in an unseen, snow-filled ditch: I snapped a Spider to the one wheel I could access and was able to drive myself out with no problem.

The one caveat is that they are not as easy to remove, since the tire flattens out a bit and moves the lock slightly off-center. I still loved them.

Car brakes have most of their power and effect on the front wheels. On a rear-wheel drive vehicle engine braking slows the rear wheels without slowing the front wheels, leaving you with much more steering control, and a bit of self-correction. The handbrake also works on the rear-wheels only (there may be exceptions to this, but I haven't driven them).

""#72 ::: Suzanne :::
Also, if someone hasn't said it (sorry, having trouble keeping up right now), don't stop half way up a hill and expect to get going again.""

Agreed. I cannot even begin to count the number of times I've been coming up one of the two hills that give access to our house, and have someone start down the hill toward me.

My only alternative is to backup using the controlled slide required in that ice and snow and try again after they have gone.

Another thing that is handy to have is a small steel putty knife ( about 4 inches wide) -- at times I have had the "opportunity" to scrape down to the bare pavement in front of the drive tires and get some traction that way (it's good for about 3 feet of running space before the slick takes over again)

And I can certainly second Ledasmom's comment about the scent of dying tires on our hill. And their death cries....

Are you sure? Engine braking is dynamically stable and thus won't lock your wheels, and can provide a pretty convenient "moderate level of braking" without requiring any driver attention at all. It also lets you do the frequently-valuable operation of "apply braking force to all wheels not being used for steering" in a rear-wheel drive vehicle. In really bad conditions you can easily get into a situation where letting off the brakes isn't enough to get the front wheels turning again and you need to straighten the steering wheel; using engine braking makes this less likely to happen.

Yes, I'm sure.

First, the issue with loss of controlled traction in slippery isn't about locking the wheels - it's about making them turn at a different speed than the road is going past.

Second, while it may be a "moderate level" of braking, it is a level that is difficult to moderate. This is because the ultimate braking force applied to the wheels is a ballet of engine resistance (which changes depending on engine speed) and clutch effects (if you've got a manual transmission).

And, while I'm sounding all snooty, I should point out that engine braking in a rear-wheel-drive vehicle is especially dangerous. This is because the rear wheels are the ones that define the yaw stability of a vehicle. If the rear wheels start skidding due to over-braking and the front ones are still happily turning, then the vehicle will very shortly be travelling backwards.

Please forgive my superior-seeming attitude. I'm a Canadian who learned to drive going to ski hills, and I'm a design engineer for Daimler Trucks North America - and I have poor impulse control in the few topics in which I have any authority.

And, while I'm sounding all snooty, I should point out that engine braking in a rear-wheel-drive vehicle is especially dangerous. This is because the rear wheels are the ones that define the yaw stability of a vehicle. If the rear wheels start skidding due to over-braking and the front ones are still happily turning, then the vehicle will very shortly be travelling backwards.

You can keep an unstable vehicle pointed the direction you want as long as you have available steering lock, but once the front wheels start sliding you have zero directional control. On the snow, where you can't build up enough force to really put high rates on the vehicle, I think that having steering is useful.

Please forgive my superior-seeming attitude. I'm a Canadian who learned to drive going to ski hills, and I'm a design engineer for Daimler Trucks North America - and I have poor impulse control in the few topics in which I have any authority.

Shrug. I use my cargo van (Ford, but those Sprinters are nice) as a ski vehicle and after doing a bit of dirt biking found that a lot of the same principles apply. The more control inputs you have, the better, and being able to control the front and rear axles independently is really useful. What kinds of trucks do you design for Daimler?

Back when a bicycle was my only vehicle, I turned off a main road into a side street. The main road was gritted. The side street wasn't. I discovered the black ice when my bicycle wheels went sideways and I rapidly practiced a side-breakfall.

I'm just really, really glad I'd let the car that had been behind me overtake me and turn first, 'cos there is no way he'd have been able to avoid me.

The astounding thing about that Portland video is the absolute refusal of all those drivers to learn from direct experience. What do they think has changed since the last time they pressed the accelerator?

Also astounding are the pedestrians, who after watching multiple large metal objects careening past in uncontrollable trajectories, fail to consider how rapidly they themselves could move in the icy/snowy conditions if they had to dodge the next one.

#83 and #85 : I shrug too. I learned to drive in England and Scotland, back when they had plenty snow in the winter. And I've done three winters in Albirda too. Ski hills, yadda yadda. You can skid just as well when it's just below freezing point as when it's -40 - better, in fact, because there's often a film of unfrozen water on top of the ice.

Engine braking works if you use it properly, just like everything else on the car. If you use it properly it's a much smoother way of braking than dabbing at the brakes, which is likely to get you into trouble if you don't get the pressure just right.
Of course you need to know which wheels are the driven (or braking) ones, but you need to know that anyway to drive on ice or snow. Engine braking with front-wheel-drive can be a bit of a balancing act, but still useful sometimes.
And of course engine braking isn't a panacea - use it appropriately, or not, according to the conditions (just like everything else on the car).

The Portland video was taken during one the of the city's rare snowstorms, not an ice storm. Problem is, the storms are too rare, maybe two a year; Portlanders don't have snow tires. Chains, man, chains.

You can keep an unstable vehicle pointed the direction you want as long as you have available steering lock, but once the front wheels start sliding you have zero directional control. On the snow, where you can't build up enough force to really put high rates on the vehicle, I think that having steering is useful.

Well, while you've got steering input you can try to maintain directional control. Unfortunately, once the rear wheels start skidding even slightly, they travel sideways just as happily as forward. This can quickly overwhelm the steering input's ability to compensate.

The more control inputs you have, the better, and being able to control the front and rear axles independently is really useful. What kinds of trucks do you design for Daimler?

It's definitely true that the more inputs the better, in a general sense. Still, for your average driver, engine braking in slippery conditions will never be as balanced or controlled as the regular braking system. Especially in vehicles equipped with ABS, and particularly in vehicles equipped with stability control. Indeed, engine braking is the one mode that virtually no vehicle manufacturer has a good system to compensate for.

Jake, my primary role currently is designing chassis systems for class-8 trucks, mostly the Western Star brand. My previous role was analysis of vehicle performance. In both cases, it's like getting paid to play all day.

John Stanning:

You can skid just as well when it's just below freezing point as when it's -40 - better, in fact, because there's often a film of unfrozen water on top of the ice.

This bears reinforcing: near-freezing temperatures are much more slippery than far below freezing. The phase change of the snow and ice into liquid due the the pressure of tires/feet/skates is what is the most treacherous. Sitting on top of shifting snow can be bad, too, but it has a far higher degree of traction, as well as a much more gradual transition between pure rolling and pure sliding.

Amusingly, I live in Portland right now, and I've been here through a couple of their freak ice storms. I can testify that the roads get plenty slippery, but that it's all made worse by people who have very little experience driving in snow. My car is all-wheel-drive, but even I look for excuses to avoid driving when it snows here - the commuters are too willing to kamikaze.

I submit to the members of the jury that this is a common attitude amongst people here, possibly more common than average, and that many of us try to or have gotten into jobs where that is one of the things we can say about them.

As for snow and ice, I live in the central belt of Scotland, and passed my test 12 years ago. I don't think I've done more than 12 hours driving in snow and ice since then. The climate change is taht severe. My mother used to drive through a foot of snow to get to work, but now the last decent snow that I can recall was in 2001. Therefore, although I know more about driving in snow than the softies we now have in the central belt, I know I dno't have the experience.

John L @ 63: I'm reminded of the time we borrowed a friend's old 1969ish Ford truck with a column-shifted transmission for hauling some things.

After the trouble I had starting out uphill with a full load of stuff -- not serious trouble, mind you, but it was a bit tricky -- I decided that I should do a little experimentation, and quickly concluded that my mom's instructions about the shift pattern weren't quite right. Somehow, she'd thought it was a four-speed rather than a three-speed, and had been driving it starting in second, shifting to third, shifting back to second, and back to third. (Given the slop in the column shifter, it was certainly easy to think those were different slots.)

> And, while I'm sounding all snooty, I should point out that engine braking in a rear-wheel-drive vehicle is especially dangerous.

Yes, someone should have pointed this out to my brother-in-law. Came over the crest of a hill and found the shadow side was icy, thought that he would skid if he braked and that engine braking would be better.
He and his wife weren't injured, and they did stop before hitting the queue of traffic at the bottom of the hill, but every single body panel of his TVR except the roof needed replacing after the resulting spin bounced them off the crash barriers.

re 81: I especially like the way (in the last clip) the fellow with the wreck patrol puts on his arrow to point people into the pile-up, therefore guaranteeing that his truck is eventually going to get hit (and it does).

One bitter experience from many years ago that I will pass on. If you try to turn at an intersection and your car just gently keeps sliding in the direction you were going, before you hit the curb, straighten your wheels. Even at very low velocity (I was well under 5mph) stopping the car by hitting the curb with the side of the wheel bends the axle, requiring a tow and expensive repairs when you should have just been able to drive away.

Any road with a significant grade gets closed. "Do Not Enter" signs are conveniently chained to stop signs and are dragged into the middle of the road to prevent unexpected auto-slalom races.

'course, if you close roads with significant grade in PA when it snows, you end up with it being illegal to drive. I've been through storms where that happened, but it's rare. It's not trivial to get a front wheel drive vehicle up a snowy 18% grade, but it can be done.

Main things I've learned: find a large empty parking lot and practice. Know what your car will do. If you do not know how your car will respond to an input, you will have serious problems. I don't care if you've got two cars of the exact same brand and model. Test both. They will be different. Ideally, you want your practice with an experienced snow driver in the passenger seat.

The half gear higher thing on a manual is about dead on. So if your car is normally happy going 5 mph in 1st, 20 mph in 2nd, 35 mph in 3rd etc, upshift earlier. You *can* start in second on a 5 speed. You probably will need to. The moment you can shift into 3rd, do it.

The combination of high gears and an 18% grade gets... exciting. I can recall two instances where getting up the hill just wasn't happening. My sister was driving a Fiero in about 8 inches of snow. This is Not Recommended, because that's about all the clearance the thing has and the handling got real funny. Dad and I walked out to get a more experienced driver (native Minnesotan) to the car, and then my sister and I walked home once he got it going. (See abi, we used the buddy system, just like you should when there's a hypothermia risk!)

The other instance, my mom and I were in our Aerostar. It was very firm that it wasn't going up *that* with 6 inches of snow on the road. Rather than arguing, mom used an alternate route with a shallower grade. Even then, she ended up using me to help weight the rear end. I wasn't old enough to drive, or we'd have swapped.

If the cars had had studs, getting up the hill might've worked with that much snow. On other cars, with other loads, I've gotten up without studs and with just as much snow. It's different every time. Do not trust snow to be the same from one storm to the next.

One thing about living in Puerto Rico -- no chance of getting caught in snow.

But when visiting friends in the mountains, I keep seeing these roads that go, like, straight up (I'm serious -- grades of 40% or more are not unusual). And every single time, literally every single time, I think, "Damn, they'll never get up that come winter."

Some years ago, my aunt and her family lived in Puerto Rico. My cousin Chacho was three. When They (I don't know who exactly, so They) decided to import snow for kids to play in, my aunt was horrified. Partly because of the idea of importing snow which would, even with the best air conditioning, become slush very quickly, partly because she knew she'd end up taking the kids because Chacho had never seen the stuff, and partly because the snow was imported from where she grew up and went to college.
We made such fun of her that year....

Well may you laugh at those Portland drivers; I've been living here for 30 years, and I see them almost every winter*. Let me tell you about the award for Most Resistance to Learning From Experience.

About fifteen years ago we lived in a house at the bottom of moderately steep hill. This meant that we had a bad drainage problem on our lot, but it also meant that I could almost always park in our driveway after coming home. One winter there was really heavy snowstorm, and I came home from work very early, intending to miss as much of the madness as possible. I had very little problem getting home, but it kept snowing, and got really deep, with dry, fluffy snow. Sometime about an hour before dark a guy who lived at the top of the hill drove up in his beatup Chevy sidepanel van. He looked the situation over, backed up to the beginning of the street (it's a T intersection) to give himself about 200 feet running start, and gunned it. He got about halfway up the hill, lost momentum, and came sliding back down. So he tried it again. And again. And again, until well after dark. At least 50 times, probably more. And each time, he'd gun it on the hill, spinning his tires madly and sliding all over the place. The next morning his truck was parked in front of our house. I was surprised not to see him still trying to get up that hill.

* Some winters we don't get snow or ice. It didn't used to be that way, but all the gasbag politicians have been heating up the planet ...

I was working at a bookstore in Denver when an ice storm came through in the middle of the day. It seems the forecasters had thought the front was going to go through Wyoming. Among the problems of the mistaken forecast was a 70+ car pileup on I-70, numerous fatalities. Ouch.

At any rate, because of the situation, I got to drive on ice for the first time in my life, 10 miles to pick up my husband. What I discovered is that I was actually doing a better job than most of the people on the road because I knew I had no experience, so I was going very slowly, paying attention to my car, and so forth. I lost control once but regained it quickly enough that if I hadn't been able to brake, I could have driven off on the shoulder to avoid the van in front of me.

Around an hour later I got a call from my husband and was able to tell him that yes, I was on my way and not in a ditch somewhere. And I was in a sedan, though we may have loaded the trunk at the beginning of winter.

Now, the amusing coda to this is the fact that this was a Friday, and our friends in Denver had a habit of getting together on Fridays, whoever showed up at a particular coffeehouse— another 10 miles from my husband's work, and about 25 miles from our apartment. In a burst of not-really-thinking, we went— and were not the only ones who showed up. Two of the ones who showed up lived about a mile from us.

We all made it to our respective locations intact, though we had one moment when we thought we were going to hit a fire truck.

Yeah. Drive as though you have no brakes. In fact, learn to drive a motorboat— the response is similar.

Jim Macdonald: If you find yourself skidding, take your foot off the brake and allow the vehicle to coast. Consider down-shifting to allow engine compression to slow you.

I'm new here. I've lurked for a long time, and have great respect for Jim, and take his experience, and his knowledgeable posts here to heart. I can only offer my own experience, which (since I'm new here) I know you longtime readers have no particular reason to trust. Here goes anyway:

I live in Montreal. I took my Driver's Ed. in 1986. My instructor emphasized, most particularly, that this is a Bad Plan. I did not (and still don't) understand the technical reasons why, but it had something to do with, 'The engine suddenly making the wheels slow right down is pretty much the same as the brakes doing it!'; he recommended putting the car into neutral during a skid, a habit I've never gotten out of. This was before ABS, of course. I only got those last year, and it took me the whole darn winter to get used to them. Braking is totally different, now.

The other stuff? Right with you. 4WD does not suspend the laws of physics - I can't remember how many SUVs have passed me in my Protege while I was doing 40kph, only for me to see them again, as I drove past them in a ditch.

Oh, and what "steer into the skid" means: the way you feel your arse going? Turn the wheel that way (a quote from the same instructor).

Emily @ 99 - Ahh, the steep grades of PA - One of my favorite motorcycle roads is PA611 (I think it's 611) on the shore of the Delaware River south of Easton. There are some surprisingly steep grades on that thing.

Michael @ 102 - The first couple of years I lived in SF, every time I drove up Potrero Hill, I thought the same thing. Of course, it does snow occasionally in SF. It never did while I lived in the Bay Area, though there were a couple of storms that completely shut down every road in/over the hills between the Bay and the Ocean.

There are times when it doesn't matter how slow you go. Once, years ago before we even had kids (wow!), we flew into Frankfurt on our way to Budapest to visit my wife's family. We visited some good friends in Stuttgart, then set out east.

It was beautiful snow. There was a lot of traffic, though, because it was late in the year and lots of people wanted to get some skiing in before it warmed up. So it was dark by the time we crossed into Austria. And still snowing.

Not willing to give up (we didn't have the money to stay anywhere), we pressed on at about five miles an hour, somewhere past Salzburg. There wasn't that much snow on the road itself, and at that slow speed I didn't think it would be an insuperable problem.

About midnight, we saw some headlights ahead of us suddenly swerve back and forth, then .. point up into the sky. And shortly after that, we were driving sideways. Then we were facing back the direction we'd come. And then we were going sideways again, and then we were going forwards, and I managed to steer us to the shoulder, where we stopped with a crump.

The driver ahead of us was from Bosnia-Hercegovina, a really nice guy. He was unscathed. We talked for a while about the amazing properties of snow, and a towtruck eventually came for him, and shortly thereafter a snowplow, which we followed for a while. At least as far as Melk, anyway, perhaps all the way to Vienna.

Must have been really patchy fog; usually the CHP runs convoys where there's fog, to keep the speed to a reasonably sane level (which is about 25mph max on freeways).

Tule fogs are odd, anyway: they're called ground fog because they're low-lying. Looking at a bank of it, it's like looking at a wall of gray cotton balls: you can tell it isn't hard, but it's opaque, or nearly so. If you're inside it and it's more than a hundred or so feet deep, it's just gray. Sun? It's a lighter gray spot. No visible shadows to speak of. You might be able to see across a street, but that's about it. Don't even think about using high beams: all you'll see is reflected light.

Very few places allow studs anymore, they wreck roads. On the other hand modern tire compounds are far better than they used to be and most premium winter tires are great without studs under most conditions. On smooth ice nothing compares to studs but smooth ice is a very rare thing non rural roads.

If you have a rear drive car then you are insane not to have a full set of winter tires if snow is likely more than a couple of days a season. They are less of a necessity on front drive cars. As a basis of comparison I drove rear drive cars here in West Michigan (lake effect land) for 15 years, till last year when I got a Civic. I always used premium winter tires and never had an accident and never got seriously stuck. I used just good all season tires on the Civic last year. It was at least 4 times easier to drive the front drive Civic in bad conditions than the rear drive cars with winter tires.

No comment on all wheel or 4 wheel drives except that most vehicles in the ditch on the interstate during the first two or three snow events here are SUV's. Jokes on them.

Like JulieB (#28), I'm in North Texas, and we haven't had much of a winter for several years, but when we have had a winter storm, it's often been in the form of an ice storm, at least somewhere on its path. I've followed much the same advice as that given by Jim, and it's served me well, except for one thing. I've found it safer to use lower gears, compared to dry conditions, rather than higher. But the only way for that to work is to keep my foot off the gas!

John Houghton (#78) gave an excellent explanation of why engine braking works well in rear-wheel-drive vehicles, but not in those with front-wheel-drive. Trying to compare the two is like comparing apples and golf balls. I've had a few small sedans with FWD, and I found that I could let the front wheels do all the work, and the back-end just follows along. The front engine helps with the traction, and as long as I kept my speed down and didn't try to make any sudden moves, I was safe. With RWD, it takes more work, making sure the back wheels don't outpace the front. Using lower gears and engine braking to slow the car down helps assure that the front wheels won't lock up, and the back won't try to swap ends with the front.

RooK's recommendations are great for those who drive expensive cars with ABS, traction control, stability control, and AWD. But suggesting that just using the brakes and letting the computers do the rest is nothing but reckless when the audience consists of people with all sorts of cars, with all sorts of equipment. I greatly prefer a method of driving that doesn't involve air-bag deployment.

All my vehicles now are pick-up trucks, with a Dodge Dakota the smallest (except two old barges that I would never take out in bad weather). I have a few bags of cement mix that I keep stacked in the garage, and when a winter storm is forecast, I put them in the back of whatever vehicle is going to be driven. My preferred method is to stay home, but if I'm forced to get out in it, I make it a point to let my rear wheels do the stopping and starting, ask the front end for permission before I go into a turn of any kind, and keep plenty of distance around me.

Those Portland and Seattle clips clearly showed that a few drivers were "blessed" with a considerable dose of stupid. I also try to remember that anyone around me might be like that.

Another rule: If you're following the sand truck down the highway, be aware that he will run out of sand. He's not driving on sand, so he won't slow down. But you're going 20 MPH too fast for an unsanded road.

One of my personal rules for dealing with dense patchy fog at night ... if the tail lights of the vehicle behind you suddenly disappear, it is time to slow down. Drastically. Do this before you reach the fog yourself. This gives the person behind you warning (because they will see your tail lights) and pretty much guaranteed, the person who just plowed into the thick-as-milk fog in front of you just hit their brakes after they entered it. Only you can't see their brake lights because they're already in the fog.

-- I'm waiting for the next bad foggy morning here in the desert flats south of Phoenix. We haven't had a really bad fog day since about 30,000 tract homes were built out here. (Before, the population was about 2,000 -- all rural country folk.) The city folk who bought the tract homes have already proven incapable of dealing with dust storms (counted ten wrecks on a half mile stretch once -- I pulled over before the storm hit) and the fog's worse for accidents than the dust, IMHO. I may just call in sick; likely, there will be accidents anyway and the roads won't be passable.

Thank goodness we don't have ice to go with the fog. I read the stories about dealing with ice here ... and it makes me glad that the worst I ever have to deal with is fog and rain and the odd dust storm.

Case one: divided highway, two lanes each direction. Two snowplows working in tandem, the left-most one forward of the rightmost one, throwing snow in front of its partner.

Visibility is poor.

Sportscar whips around me (I'm following the right-hand plow at a reasonable distance) and around the right-hand plow. Discovers that the left lane is blocked by a big yellow truck, and cuts sharply right in front of the right-hand plow, and directly into unplowed snow, with a lane's worth of additional snow recently added. Car contacts blade. Badness ensues.

Or....

Nice young person and friend are heading one way on two-lane blacktop, snow falling. They have the middle of the hood right on the double-yellow line "for safety."

They see a plow truck coming, in its own lane, maintaining course and speed. It has strobe lights going.

They figure it's going to get out of their way. It doesn't. When she figures this out she turns out of the way, goes across the road and into the guard rail. No serious injuries (young people were wearing seatbelts, yay!, but the young person spends quite a bit of time trying to get the state trooper to agree that the state owe hir a new car because the state wrecked this one.

Just a reminder that on the wet coast "AquaTreads" style of all season tires are beyond useless even in the rain season let alone the ice season. I'm not kidding folks do try to drive those things in snow.

Victory is ours, comrades! For an encore, let's convince him the efficacy of applying leeches to reduce "heated spirits".

LMB MacAlister:

RooK's recommendations are great for those who drive expensive cars with ABS, traction control, stability control, and AWD.

I assert that my reasons are just as valid in plain old non-computerized vehicles. That's the reason why many manufacturers would put disc brakes on the front and drum brakes on the rear* - because the superior disc brakes would cause skidding first. This is safer from the manufacturer's point of view because skidding front wheels means you slide nose-first into things - which allows seat belts, crumple zones, and (if you have them) air bags to do their work. Plus there's the clinging hope that you could eventually reduce tire forces (like reduce brake pedal pressure) and resume steering control. Skidding rear wheels means that attitude control is lost and the vehicle is going to impact things in a random orientation - including a greater risk of rollover - and there's pretty much no chance of recovering control any more.

the reason why many manufacturers would put disc brakes on the front and drum brakes on the rear

I thought it was because (a) in the early days, discs were more expensive than drums, so the manufacturers, being cheapskates, put discs only on the front wheels because (b) under heavy braking the deceleration causes the weight (or centre of mass) to shift forward so that there's more weight on the front wheels, so that better braking on the front wheels has maximum effect, and also because (c) disks are more predictable than drums, less likely to cause differential braking (braking more on one side than the other) which, at the front, is bad news.

But 'heavy braking' is what you do in an emergency on a good surface, not on snow or ice.

...let's convince him the efficacy of applying leeches to reduce "heated spirits".

Well, they are effective. Medical leeches are still in use today (for certain very specialized applications). For that matter, if you fully understand the four humors and apply that understanding rigorously, you're well on your way to doing good field medicine. The human body really is all about balances. If it's too hot, cool it. If it has too little blood, add some. And so on.

The combination was unexpectedly dense fog in a very narrow band, running north from Corcoran to just south of Fresno, where it cut across 99. It happened at 8am with lots of weekend commuters and trucks out, thinking that the fog was rather light, so they didn't slow down. When it was over they needed a crane to get a truck off one car so they could extract the occupants, and the Northbound lanes of 99 didn't reopen for 12+ hours. It was fortunate that only two died. Collisions continued after emergency crews started work.

There are ground fogs in many places but the genuine Tule fogs are something else. You watch for a particular set of conditions: Little if any wind, damp ground, warm afternoons, cool to cold nights. For example, if it has been overcast for several days, fog may not form as the ground is simply not warm enough to generate enough water vapor. Local conditions are important and there are some stretches that are particularly bad. Most notorious are the stretches around Tulare and Chowchilla -- and I currently commute through the Chowchilla area.

One problem is that people tend to look out for thick fog, not thinking that by the time you can tell it is that thick, it may be too late. What you often get around here is a light fog, with very dense patches. Cars regularly pass me on 99 roaring on at 80 mph in a light fog. The problem is that a dense bank is invisible in that light fog until you are in it.

When I was commuting into the Bay Area, when it got too bad I would pull off at a coffee shop, pull out the laptop and cell phone and let the office know I would be at least an hour late. Somehow, people just don't consider how dangerous it is on a freeway in those conditions.

I can vouch for the scariness of Ledasmom's and Craig R's hill. I'm as experienced a snow/ice driver as they come in the contiguous 48, and I'm very glad I don't have to tackle their hill in the snow.

Actually, I'm far more likely to stay home in bad weather when I'm in the South than when I'm further north. 1) More ice and slush 2) Less experienced drivers. It's not the driving conditions that scare me half so much as the locals on the road. I've never viewed driving down a snowy hill the same way since our office manager in Nashville confided her surefire way for getting up a slippery slope with sliding cars blocking the route up - gun the motor, get going as fast as you can, and go up the left-side lane.

It never seemed to occur to her that the five cars she had totaled in eight years might have something to do with her driving technique.

An ther come landles men of il wil, grete storms, peste, Upheavel of Earth, Campbells, the Turke, Malefic Vapours or siccan ither perils, shoult ye have preparit a bag, and see it stand by the door, that ye maist sieze it as ye fly:

i gude cloke of englysshe wool with a hode to it
i box of tinder, an it be wel sealit
i flint (for Fyre)
i lanthorn
ii quil pens (for certes yow shal lose i)
i bottel ink of Indie
some piece of parchement, vellum or what you wil
i dirk, dagger or misericord
a good length of Cord or Rope
such gowd as you may spare

Materia Medica
iv leechis (for the amendement of Humours)
i bottel aqua vitae (for the amendement of Spirits)
India Pepper, or Cayen
iii glas vessel for Cupping
sundry rags for the binding of hurts
comfrie, for a Poultis
Saint John his Wort, for the Heart

Victuals
iii piecis salt fysh
ii lb oatmele or barlecorn, in a Sack
i chees
i lethir bottel for water
(an forget not a good iron Pot or Kettel, says my Goodwife Doyle)

Rook @ #124: You don't do your unified case much good with this sort of thing, either: Skidding rear wheels means that attitude control is lost and the vehicle is going to impact things in a random orientation - including a greater risk of rollover - and there's pretty much no chance of recovering control any more.

You've never heard of opposite-lock? The technique is the first advice given to drivers in a skid: steer into it until you regain control. It's right there in the links at the start of the thread.

You've never heard of opposite-lock? The technique is the first advice given to drivers in a skid: steer into it until you regain control. It's right there in the links at the start of the thread.

Opposite lock is a means to attempt to regain directional of a vehicle by trying to regain attitude control. Full opposite lock on my car is 45° - what do you think happens when the car's attitude exceeds this angle? Flat spin. This is what I meant by "random orientation", and there really is pretty much no chance of recovering from a flat spin in a timely manner.

Backing this chain of events up step by step:
· Avoid flat spins by avoiding exceeding what reverse lock can scramble you back out of.
· Avoid needing to execute reverse lock by avoiding having the back end step out.
· Avoid having the back end step out by avoiding having the rear wheels skid.
· Avoid having the rear wheels skid by avoiding unbalanced, poorly-modulated braking forces applied to the rear wheels.

Having grown up only a few hours from Fresno, in another of the coastal valleys, I still remember tules - convection fog, oh my. Actually, I've seen a very mild form in some places in the San Fernando valley - the cemetery south of Burbank Airport (the one with the fancy domed monument and the scale-model Shuttle) gets a version that involves either rain or their sprinkler system.

[/lurk]
Niall @ 129.
Rook's previous posts have been dead on the money in terms of the physics of the situation.

In low traction conditions, when a car loses traction on one end (either end) inertial effects dominate. In those conditions twiddling the steering wheel doesn't allow you to regain control, it just - at best - allows you to have some say about vehicle orientation - not direction - until you encounter a patch of road where traction is good enough for friction effects to become dominant again, which hopefully occurs before you encounter some scenery. At which point normal service will be resumed, and the slide can be sorted out. The point being all skid control techniques rely on the availability of a reasonable amount of lateral friction or a huge amount of real estate.

Which isn't to say that its impossible to lose traction on ice and recover, or that using engine braking will automatically kill you, or even that a decent driver can't make use of it, just that it's not the optimum tool for the conditions.

disclaimer: Haven't driven on snow or ice in years. On the other hand, once upon a time I used to design car suspension and braking systems for a living. It's been a while, but the physics hasn't changed.

Rook @ 91 "it's like getting paid to play".
Ain't it though.

James @ 96: "It's likely he'd have skidded if he braked, too"
Probably not, in a TVR. It's the perfect vehicle to demonstrate Rook's point. Light weight, short wheelbase, massive high-compression motor and short gearing - taily as all heck on the overrun, and when it gets out of sorts, everything turns to custard real fast.

May I add a recommendation for your nearest "Skid School". I sent each of my boys as a 17th birthday present. They are 29 and 31 now, avid snowboarders. No bent sheet metal and best of all no scuffed up boys. The school uses cars equipped with casters on outriggers with hydraulic goodies that allow the instructor to simulate ice. Both my young men say it was valuable. It was about $150 at the time. I see in Portland it's about $300. A significant cost but money well spent.

At least three people in Minnesota, three in Wyoming and one person each in Texas, Kansas and Wisconsin were killed in traffic accidents that authorities said stemmed from the storm.

The fatality in Texas came in a chain-reaction pileup involving more than 50 vehicles, including several tractor-trailer rigs, on Interstate 40, police said. At least 16 people were taken to hospitals, Sgt. Michael Poston said.

"We're not really sure how many cars, probably in excess of 40 cars and in excess of 20 semitrailers," Amarillo police Sgt. Greg Fisher said Sunday.
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Many were holiday travelers, including families with small children not dressed for the weather, Sgt. Shawn McLeland said. Other drivers opened their own Christmas presents to provide warmer clothing for the children.

Authorities believe the pileup, which shut down the highway for most of the day, was caused by near zero visibility in blowing snow and slippery pavement. Multi-vehicle wrecks on Saturday also blocked sections of I-70 in Kansas and I-29 in Missouri.

Thanks for pointing to that, Lori Coulson. I'm in Seattle, and you may have heard that we're having Weather. People in Seattle are much less prepared for snow than those in some other places; fortunately, my partner Karen has much more experience driving in snow than I do.

I'm avoiding driving until it gets warmer (probably tomorrow). It's very pretty, though, from inside the house. We've brought in the cat who lives with an elderly neighbor six blocks away (long story), and he seems very grateful.

"It's scary," Esther Boyer told CNN affiliate WDTN, soon after her car slid into a ditch Friday in western Ohio. "I guess I was just driving too fast, and you should slow down a lot sooner."

The lone blizzard warning, in effect Friday night through 6 p.m. Saturday, was for parts of northern West Virginia and north-central Maryland. The National Weather Service predicts 8 to 12 inches of snow and sustained winds of up to 35 mph, with gusts blowing up to 60 mph.

If you do have to drive during the storm, police say to keep extra distance between yourself and other cars. They say you should also carry an emergency kit in case you do get stuck and have a long wait. That kit should include warm clothing, boots, a blanket, a snow shovel, and tools to clear snow off your car. Police say it's also a good idea to carry rock salt, flares, and a charger for your cellphone.

PJ Evans @151, actually, according to NPR a few minutes ago, they've pulled the snowplows in Texas and/or Kansas (sorry; memory from radio; not sure which) back to the barn because the state thought that the drivers were at risk.

153
The people in Texas expect it to clear out tonight, so probably it's the ones in Kansas that got called back to the barns.

In winds like that, I want to be in a basement. For one thing, it's a lot quieter.

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